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Home >> Hyundai >> 2003 >> XG350 Base >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Controls - System & Component Testing >> Sensors & Switches >> Sensors >> Engine Coolant Temperature (ECT) Sensor
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Engine Coolant Temperature (ECT) Sensor

  1. Turn ignition on. On Accent, Elantra, Santa Fe, and XG350, backprobe and measure voltage between ECT sensor connector terminals No. 1 and 3. On Sonata and Tiburon, backprobe and measure voltage between ECT sensor connector terminals No. 1 and 2. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. On all vehicles, compare voltage with expected value. See ECT SENSOR SPECIFICATIONS  table.
  2. To check sensor resistance, turn ignition off. Carefully remove ECT sensor. Immerse sensing portion of ECT sensor in water and heat water. On Accent, Elantra, Santa Fe, and XG350, measure resistance between ECT sensor terminals No. 1 and 3 as water is heated. On Sonata and Tiburon, measure resistance between ECT sensor terminals No. 1 and 2 as water is heated. On all vehicles, compare resistance with expected values. See ECT SENSOR SPECIFICATIONS  table.
ECT SENSOR SPECIFICATIONS

Temperature °F (°C) Ohms (1) Output Voltage
14 (-10) 8160-10,740 (2)
32 (0) 5180-6600 4.05
68 (20) 2270-2730 3.44
104 (40) 1059-1281 2.72
140 (60) 538-650 (2)
176 (80) 298-322 1.25
194 (90) 219-243 (2)
(1) Backprobe ECT sensor connector or ECM connector during engine operation.
(2) Value is not available from manufacturer.